1. Field of Invention
The invention relates to a technical medical device, in particular a blood treatment device having at least one touchscreen and a method for display and input of information in a blood treatment device having at least one touchscreen.
2. Description of the Prior Art
Technical medical devices with touch-sensitive displays (touchscreens) as a means for simultaneously displaying information and receiving operator input are widely known in the state of the art. One example of such a technical medical device is the Hemodialysis Machine 5008 from Fresenius Medical Care.
Technical medical devices having touchscreens offer the user a convenient, variable and hygienic user interface due to the flat unbroken surface.
Touchscreens for technical medical devices have so far offered essentially only smooth flat surfaces. The operator recognizes the area of the display where a fingerprint is expected based on visual display of a control panel. There is no tactile acknowledgement of whether the expected area has been touched. Such tactile feedback is offered by conventional mechanical switches with which operation requires a tangible application of force and/or with which operation can be sensed by the actuator travel. One disadvantage of such mechanical switches due to their design is their property of frequently breaking through the surface of the technical medical device, which makes hygienic cleaning of the surface difficult. In addition, mechanical switches do not offer the variability of a software-controlled switching matrix of a touchscreen, which offers flexibility with regard to varying the number, size and position of the virtual switches on the touchscreen.
For the safety of a technical medical device, it is essential for the input and display of information on a touchscreen display to function reliably and unambiguously.
For this purpose, it is advisable to have a redundant design of the input option via the touchscreen by providing another input option for important information in the event of failure of the input functionality of the touchscreen, for example, for safe termination of a patient's treatment. In the state of the art, this is made possible by additional mechanical switches or buttons, for example. The properties mentioned above with regard to mechanical switches have proven to be a disadvantage in this regard.
Devices having a touchscreen with tactile feedback are known from the field of telecommunications and computer technology. WO2009/085060 describes one such device.
Tactile feedback is obtained with such devices in order to impart the feeling of a mechanical button to the user when he applies his finger to the touchscreen display. This constitutes a gain in convenience in particular when the device has no mechanical keypad but instead has only a touchscreen such as that on various mobile telephones or minicomputers. In these applications, convenience of use is the primary concern, but technical safety advantages are not achieved by a touchscreen having tactile feedback with the known devices.
However, the safety aspect is of primary concern with technical medical devices.